Disablement affects about 40% of patients in the late stages of cancer, devastates their quality of life (QoL), and radically increases healthcare costs. Data strongly suggest that proactively treating the causes of cancer- related disablement; physical impairments, pain, and related immobility, can significantly prolong patients' functional independence, improve their QoL and avoid unneeded expensive and extended hospitalizations. Current rehabilitation service delivery models are reactive in nature and tend to focus on catastrophic disability, characteristics that render them ill suited to detect or address early disablement in cancer or any vulnerable patient group. An empirically validated collaborative approach to pain care, the three component model (TCM), optimizes important clinical outcomes and may provide an ideal framework to overcome barriers to the timely integration of rehabilitation services into cancer care. However, the TCM, given its pharmacotherapeutic focus cannot be directly applied to rehabilitation and its need for in-person interaction. We have, therefore, developed a novel extension of the TCM that targets disablement by engaging local physical therapists to address patients' physical impairments and related immobility. Preliminary work shows that this extension (TCM-Rehabilitation Services (TCM-RS)) is highly effective and well received by patients and local therapists. We propose to rigorously examine its effectiveness and costs among 495 patients with late stage cancer in the COllaborative Care to Preserve PErformance in Cancer (COPE) Trial. Since pain is strongly implicated in cancer-related disablement, optimized pain control may maximize the TCM-RS' benefit. COPE will therefore include, in addition to the two arms of; 1) enhanced usual care, and 2) rehabilitation services targeting physical impairments and immobility via the TCM-RS, a third arm; 3) TCM-RS plus conventional TCM pain management TCM-RS+Pain. Participants will undergo an initial 4-week intervention period and then be followed for a total of 6 months with the trial's primary outcome, functional status, and two secondary outcomes, pain and health utilities, being assessed monthly via an automated, telephonic monitoring system. Additional outcomes; QoL, physical activity, and caregiver burden, will be assessed at baseline, 3, and 6 months. Costs will be abstracted from clinical records and administrative databases. Our objective is to estimate the effectiveness, as well as the cost-benefit and -utility implications of the TCM-RS and TCM- RS+Pain in order to inform future research and policy in the means to minimize functional loss in chronically diseased populations.